I didn't refer to any of your 20,000 rounds, give or take. The Glock 21 is still the only .45 ACP pistol that I have seen a bulged .45 ACP case from. It was a Remington 230gr FMJ. The bulge was so bad, it wouldn't go into a re-sizing die.

Ammo from that same box was fired in a Colt 1911A1 and the case was still shaped the same as before it was fired.

I don't know what to tell you, other than you may have gotten a defective piece of brass.

I have had .45 ACP brass not go into a .45 ACP case gauge, but the brass was mixed and some had most certainly been fired in 1911s I used to shoot 1911s.). Some of the brass was much used, so excessive expansion is certainly a possibility. Just about all of those cases failing the check chambered and fired just fine in a G21. Still, none were visibly bulged.

As an aside, I've never had a problem with .45 GAP brass fired in one of my Glocks--or the once-fired GAP brass a GT member helped me score. All fit easily after resizing.

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